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ClaimsPrincipalExtensions

Namespace: RA.Utilities.Authorization.Extensions

The ClaimsPrincipalExtensions class provides a set of convenient extension methods for the ClaimsPrincipal object, simplifying common claim-related tasks.

🎯 Purpose​

The ClaimsPrincipalExtensions class is a static helper class that adds several convenient methods to the standard ClaimsPrincipal object. Its primary purpose is to simplify and standardize the way you interact with a user's claims.

Instead of writing repetitive code to find, parse, and validate claims, these extension methods provide clean, readable, and reusable shortcuts.

✨ Available Methods​

GetUserId()​

This is a standout feature. It safely retrieves the user's ID from the NameIdentifier claim and attempts to parse it into a Guid. If the claim is missing or invalid, it throws a clear exception. This encapsulates error-prone parsing logic into a single, reliable method.

Returns: Guid Throws: ApplicationException if the claim is missing or cannot be parsed into a Guid.

var userId = User.GetUserId(); // 'User' is the ClaimsPrincipal from HttpContext

FindFirstValue(string claimType)​

This method acts as a null-safe wrapper around the built-in FindFirstValue, ensuring your code doesn't throw an exception if the ClaimsPrincipal object itself happens to be null.

Returns: string? - The claim value or null if not found.

var email = User.FindFirstValue(ClaimTypes.Email);

HasClaim(string claimValue)​

Checks if the principal has a claim with the specific type "claim" and a matching value. This is useful for simple permission checks.

Returns: bool

if (User.HasClaim("CanDeleteUsers"))
{
    // ... perform action
}

HasScope(string scopeValue)​

Checks if the principal has a claim with the specific type "scope" and a matching value. This is commonly used in OAuth 2.0 / OIDC scenarios.

Returns: bool

if (User.HasScope("api.read"))
{
    // ... allow read access
}

These extensions are used by the AppUser service to build its higher-level, user-friendly API, but they are also available for you to use in any part of your application where you might be working directly with a ClaimsPrincipal.